Pun-Off With David

This is completely cheesy...forgive me...his family must really be wearing off on me.

Diana: So what's a sink hole? (we were watching Quantum of Solace).

David: (he said something like this) There is a pocket of earth that was filed down from water or sediment and the top of the earth eventually caves in around it...well I think so anyway.

Diana: oh you SINK SO?

David: Haha, so that was your HOLE plan all along?

Diana: Yeah, I guess it BOTTOMED OUT

David: You could say it FELL THROUGH

Diana: It was a real SINKER.